(1) Field of the Invention
Automotive brake maintenance lathes such as those manufactured by Ammco are fitted with expandable rubber or plastic bellows which serve to prevent the entry of cutting debris, dust dirt and grit from their operation into the rotating machinery of the lathe. These bellows are soft and vulnerable to other tools, such as grinding wheels, which are used in conjunction with the lathe in normal final, non-directional surfacing operations. These tools are often applied to parts held on the shaft of the lathe, such as brake disks, in order to impart the recommended swirl pattern to their surface. In such operations there is a danger that the wheel, which is hand held, will slip off the part being refinished, and will cut the above mentioned bellows or boot, thereby compromising its integrity and ability to shield the machine from damaging materials.
Repairs made necessary by the entry of such materials are costly both in terms of the labor and replacement parts costs, poor and inaccurate operation of the precision machine, and in terms of down-time of a productive machine.
(2) Description of the Prior Art
While other inventions have confined the dust and particulates resulting from the function of a brake lathe so as to protect the user from their harmful effects, as in U.S. Pat. No. 4,514,936 issued to Hurtado, the prevention of damage to the machine has been limited to a protective expandable boot which is not protected from the sharp or abrasive tools and cutters used in normal lathe operations.